body{
    background-image: url(../img/表格背.jpeg);
    /* background-position: 100%; */
    background-size: cover;
}
table tr:nth-child(1) td{
    color: black;
    font-size: 20px;
}
td{
    text-align: center;
}
table,tr,td{
    border: 1px solid black;
    border-collapse: collapse;
    text-align: center;
}
.dan{
    width: 200px;
    height: 100px;
    margin-top: 40px;
   border: 1px solid black;
   border-collapse: collapse;
}
.ni{
    width: 300px;
    height: 200px;
    position: absolute;
    top: 10px;
    right: 0;
}

